Automatic firearm.



N. BJURGUM.

AUTOMATIC FIREARM.

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AUTOMATIC FIREARM.

APPLIGATION FILED AUG. 22, 1910.

1,007,91 1 Patented Nov. 7, 1911.

BJ'ORGUM.

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APPLICATION FILED 11116.22, 1910.

Patented NOV.7,1911.

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AUTOMATIC FIREARM. APPLICATION FILED AUG. 22, 1910.

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' AUTOMATIG FIREARM.

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N. BJ'O'RGUM.

AUTOMATIC FIREARM.

APPLICATION FILED AUG.22, 1910.

1,007,91 1 Patented N0v.7, 1911.

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N. BJURGUM. AUTOMATIC FIREARM.

1 ,007,9 1 1 I APPLICATION ILED AUGY. 22, 1910.

Patented Nov. 7, 1911.

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Patented Nov. 7, 1911.

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N. BJ'GRGUM, AUTOMATIC FIREARM. APPLICATION FILED AUG. 22, 1910.

Patented Nov. 7, 1911.

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N. BJURGUM.

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1 ,007,9 1 1 Patented Nov. 7, 1911.

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AUTOMATIC FIREARM.

APPLICATION FILED AUG. 22, 1910.

Patented Nov. 7, 191 1.

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BJURGUM. AUTOMATIC FIREARM. APPLIUATION FILED AUG. 22, 1910.

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N. BJURGUM. AUTOMATIC FIREARM.

APPLICATION FILED AUG. 22, 1910.

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AUTOMATIC FIREARM.

APPLICATION FILED AUG. 22, 1910.

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' NILS BJoRGum, or ASKER, NEAR GHRISTIANIA, NORWAY.

Specific ation of Letters Patent.

Patented Nov. '7, 1911.

Application filed August 22, 1910. Serial No. 573,442.

To all whom it may concern:

Be itknown that I, NILs BJoRGU a subject of the King of Norway, residing at Asker, near Christiania, Norway, have invented certain new and useful Improvements in Automatic Firearms; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled'in the art to which it appertains to make and use the same, reference being had to the accompanying drawings,-and to letters or figures of reference marked thereon, which form a part of' this specification.

My invention relates to automatic fire arms of the kind, in which the barrel, when fired, is firmly closed by means of a rotatable breechbolt, having lugs cooperating with lugs on the barrel or on an extension of the same, so that the barrel and the breech-bolt in the first part of the recoil action travel together rearwardly, whereupon the barrel is released from the breech-bolt by a rotation of the latter and the breech-bolt allowed to continue its travel. v 7

My invention relates to the several parts and mechanisms constituting an automatic arm, and whereas the invention is in the following description described especially in its application to a so called machine gun,

the improvements may for the greater part i also be applied to other arms for instance pistols and hand guns.

In the following I shall describe my improvements reference being had to the accompanying drawings which illustrate one form of my invention. In order to facilitate the description and the understanding of the several devices the figures of the drawings are grouped so that each group specifically refers to special devices or groups of devices; but although the drawings referring to a single group are suflicient for the un-.

derstanding of the devices described under said group, reference may also partially be made to figures relating specifically to other groups of devices. In order to simplify the drawings the figures in each group as much as possible are limited to the devices described, the other devices being partly omitted or broken away.

In said drawingsFigure 1 is a vertical longitudinal section through the rear part of the barrel and the front part of the breech bolt, showing the mechanism locked. Fig.

2 is a cross section on line II-II of Fig. 1. Fig. 3 is a horizontal section on line IV-IV of Fig. .4. Fig. 4 is a cross section on line III III of Fig. 1. Fig. 5 is a view similar I to Fig. 1, but showing the parts opened and the barrel in'its arrested position. Fig. 6 is a cross section on lines VI- VI of Fig. 5. Fig. 7 is a horizontal section, showing the breech bolt in more retracted position. Fig. 8 is an end view of the barrel sleeve. Fig. 9 is a view like Fig. 1 but showing a modification applicable especially to pistols. Figs. 10 to 13 are views of the breech bolt head, Fig. 10 being a right hand view, Fig. 11 a front end view, Fig. 12 a rear view, and Fig. 13 a top view of Fig. 10. Figs. 14 and 15 are longitudinal section and cross section respectively of the breech locking mechanism as especially designed for hand guns. Fig. 16 is a detail longitudinal section. Fig. 17 is a cross section on the line XVIIXVII of Fig. 16. Fig. 18 is a longitudinal section of the breech part of the pistol in locked position. Fig. 19 is a detail. Figs. 20, 21, 22 and 23 are side view, rear view, topview and front view, respectively of the breech bolt head. Fig. 24 is a vertical longitudinal section through the breech part of a gun, showing the parts in locked position. Fig. 25 is a similar view showing the parts, when the barrel has its rearmost position and in the moment, when a new cartridge is being pressed into the chamber. Figs. 26, 27, 28 and 29 are detail views of the arresting piece looking from below, from the side, from above and from the rear respectively. Figs. 30 and 31 are detail views of the bottom piece serving to lock the stopping piece in position. Fig. 32 is a side view and vertical sectional view of the breech part of the gun showing the parts at rest, immediately after the firing of the gun. Fig. 33 is a similar view showing the position of the parts just before the barrel has ceased to recoil. Figs. 34 and 35 are side and end views respectively of the recoil lever. Figs. 36 and 37 are side and end views respectively of a portion of the barrel sleeve. Fig. 38

is a cross section on the line A-A of Fig.

32. Fig. 39 is a vertical longitudinal sec-.

- front'end view of the same.

'ing the opening operation.

spectively of the cocking .sleeve. Figs. 42

trigger guard with parts connected therewith for firing the gun by hand; Figs. 48 and 49 are sectional side views (looking from the left) of the trigger and sear mechanism and connected parts, showing especially devices coming into operation when the breech is opened by hand, Fig. 48 showing the parts when the gun is locked and has been fired and Fig. 49 showing the parts dur- Figs. 50, 51, 52, '53 and 54 are vertical longitudinal sections through the breech portion of the gun showing the cartridge conveyer in operation at five different stages. Figs. 55, 56, 57, 58 and 59 are vertical section, bottom, side, top and cross section respectively of the conveyer. Figs. 60, 61 and 62 are bottom, side and top views respectively of the conveyer lever. Figs. 63, 64 and 65 are views from the left, from the end and from the right respectively of the retaining hook of the conveyer. Fig. 66 is a left hand side view, partially in section, of the whole breech bolt with parts carried thereon. Fig. 67 y is a Fig. 68 is a right hand side view similar to Fig. '66. Fig. 69 is a rear end view of the same. Fig. 70 is a vertical axial section through the feed box and the breech part of the gun. Fig. 71 is a top plan view (partially in section) of the feed box with the driving lever. Fig.

72 is a perspective view -of the cartrid e support. Fig. v73 is a cross section on t e line BB of Fig. 70, showing the feeding mechanism in its projected position, and the cartridge in position to be gripped by the conveyin device. Fig. 74 is a horizontal section t rough the feed box on line C-C of Fig. 73. Fig. 75 is a perspective View of the driving arm. Fig. 76 is a perspective view of the pusher spring. Fig. 7 7 is a perspective I view of the slide. Fig. 78 IS a perspective of a member of the belt. 60

view of the pusher. Flg. 79 is a perspective view of the guide piece for the driving lug of the driving arm. Fig. 80 is a perspective view of the end of the barrel showing the coupling, hooks for the guide piece of the feeding mechanism. Figs.8l and 82 are cross section and longitudinal section respectively Figs. 83 and 84 are end and side view respectively of a member of the belt. Fig. 85 is a longitudinal section through a belt member in which a cartridge is inserted. Figs. 86 and 87 are end and plan views respectively of a row of belt members, the upper two carrying cartridges. Figs. 88 and 89 are end and plan views respectively, of a single member drawn on a smaller scale. Fig. 90 is a vertical longitudinal sectional view of the breech showing the parts when the mechanism is locked. Fig. 91 is a similar view. with the mechanism open and in the moment the shell is acted upon by the ejector and thrown out.

Fig. 92 is a cross section through the breech casing frame on line DD of Fig. 94. Fig. 93 is a top plan view of a portion of the same. Fig. 94'is a vertical longitudinal section through the same. Fig. 95 is a horizontal section. Fig. 96 is a. central longi- I tudinal vertical section of the rear end of the gun on a reduced scale. top plan of thesame.

Fig. 96 is a Fig. 97 is a side 1? view of the hind part of a 'gun, and Fig. 98 11" the is a top view of the arm rest and part 0 I gun. Fig. 99 is an elevation, looking from the front,'of the arm'rest on an enlarged scale. Fig. 100 is a vertical longitudinal section on the line DD of Fig. 94. Fig;

101 is a top View of Fig. 100. Fig. 102 and Fig. 103 are a side 'view and top view of the latch.

My improved breech-closing devices belong to th'e'class having a locking member capable of a movement independent of the breech-bolt proper or slider. According to my invention the slider consists of a body with only rectilinear movement and carries at its front end a short locking head capable only of rotary motion relatively to the body of the breech-block. The barrel may have long or short travel, but when it reaches the end of its travel and is .released from the locking head, it is arrested and remains at rest until the breech-bolt returns and again brings it to its forward position. It will be understood that the movements of the breech-bolt and its head are exactly alike backward and forward, only that they are reversed. The breech-bolt comprises a head 1 and a slider 2, the latter having a rectilinear movement in the breech casing and the former a rotatory movement on the slider 2.

The breech-bolt head 1 is provided with three locking lugs 3 and a guiding lug 4, (.Figs. 10 to 12) which latter projects into a groove 5 .(Figs. 4, 6 and 7) in the breech casing or frame a.

6 designates a sleeve screwed on the rear end of the gun barrel b, and provided with three lugs 7 corresponding with the lugs 3 on the breech bolt head, so that the latter lugs may be moved axially past the lugs 7 and then by a rotatory movement of the breech-bolt head be turned so that they come in front of the lugs 7, thereby effecting the locking up of the breech.

The breech-bolt head 1 fits onto a hollow pin 8 forming the front end of the slider "2, so that the head may turn on said pin. The 

